Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf8e44a252d1836c…

MALICIOUS

PDF

74.2 KB Created: 2021-09-10 20:27:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 5b8437242868186b76be6ed63608abca SHA-1: 062eea230bbbd37b154df8d1b940cef481aa56a8 SHA-256: bf8e44a252d1836c576155c6347a441128c84ae36e14915c28a430b1244fdb7f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and numerous external links, many hosted on compromised or disposable domains, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to exploit vulnerabilities or redirect users to malicious sites. The presence of embedded JavaScript points to its use in executing malicious actions within the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://oniceh.ru/uplcv?utm_term=calculator+plus+for+android PDF link annotation
    • http://resumesfromabove.com/userfiles/file/33545452684.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/43279958061374b32aa2b8.pdfIn PDF document text
    • https://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/7882e0c242d8fbf0a00f600b5c4a4d99/43938764035.pdfIn PDF document text
    • https://a-1commercialkitchenservices.com/ckfinder/userfiles/files/60677794061.pdfIn PDF document text
    • http://yuli-china.ru/d/files/29367408453.pdfIn PDF document text
    • https://esprimagroup.com/userfiles/file/91288642464.pdfIn PDF document text
    • http://chickenwild.com/upload/contents/images/images/31208338995.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/t34sonn50dmlm9nte05tqvgrfa/wijer.pdfIn PDF document text
    • http://oxigensupplies.com/shipinc/userfiles/files/63413004117.pdfIn PDF document text
    • http://sashtraayurveda.com/ckfinder/userfiles/files/pejilidiperoz.pdfIn PDF document text
    • http://titibbs.xyz/js/ckfinder/userfiles/files/26724992788.pdfIn PDF document text
    • http://mid-europe-ex.com/images/blog/file/noferenobalugapugel.pdfIn PDF document text
    • http://iwayman.com/uploadfiles/file/210905225234515893es4mgp.pdfIn PDF document text
    • https://jerseyshorepirates.com/userfiles/files/nazaxilafubada.pdfIn PDF document text
    • http://asavn.vn/uploads/userfiles/files/nudaxen.pdfIn PDF document text
    • https://www.champagne-cornevin.fr/ckfinder/userfiles/files/56938333170.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/89190713307.pdfIn PDF document text
    • http://littlepearlbooks.in/data/eimages/file/linejes.pdfIn PDF document text
    • http://119pump.net/d/files/15940540920.pdfIn PDF document text
    • http://nanobubblevietnam.com/uploads/userfiles/file/deboxagumozufepasipasofi.pdfIn PDF document text
    • https://naves.cz/res/file/14065693687.pdfIn PDF document text
    • https://postelezmasivu-liberec.cz/ckfinder/userfiles/files/6321042675.pdfIn PDF document text
    • http://china-hold.com/UploadFile/file/20210908181516711.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/06d15idhjebphl3nhnp52uj4hi/11766374179.pdfIn PDF document text
    • https://euinsuti.ro/app/webroot/files/userfiles/files/nixutafulipubunofo.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c039.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC039 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d850.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD850 10612 bytes
SHA-256: 9678962f35a0d201b5b99585614f6388cc122e935967d0a1b59b783c0757eea4
font_02_sfnt_off0000f0ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0AE 16708 bytes
SHA-256: ca7ab559a0b2799d9a47f4a390b5012938d232c86fea9caab94366fbc06bd0e2